1. Field of the Invention
The invention relates to the field of communications. More specifically, the invention relates to communication networks.
2. Background of the Invention
Control card redundancy improves reliability of network elements. Having a secondary control card with the same information as the primary control cards enables a network element to withstand hardware and/or software failure on the primary card. In addition, the secondary control card enables maintenance of network elements. The primary control card can be pulled for repairs or testing because the secondary control card will take over operations.
To avoid interruptions in service, consistency must be maintained between control cards. Information received by the primary control card is passed to the secondary control card. After the information is stored on the primary control card it is copied to the secondary control card.
This prior art technique has the disadvantage of exposing the network element to disruption. A failure may occur before information is copied to the secondary control card. When the secondary control card takes over operation of the network element, the secondary control card will be lacking information. The network administrator will have to discover the inconsistencies and correct these inconsistencies. In addition, the inconsistencies may cause service to be disrupted to a customer.